This project focuses on the development of a robust and efficient method to isolate human DNA from stool for fecal DNA screening of colorectal cancer (CRC). CRC is the second deadliest cancer in the USA and early detection is the key to eradication of this disease. Existing methods are neither sensitive nor noninvasive, leading to a low patient compliance rate. The needless death from CRC that occurs as either not sensitive or invasive, leading to a low patient compliance rate. The needless death from CRC that occurs as a consequence of this low rate of screening makes correction of the problem an urgent social priority. Fecal DNA testing is emerging as 1 of the most promising methods for CRC screening. However, a major technical barrier to fecal DNA testing has been that the quantity of the tumor-derived DNA isolated can be low, making screening both less robust and less sensitive. We recently discovered a new method, with which the stool DNA capturing was readily improved by 4-32 fold and over 50% of human DNA were robustly recovered. The aim of Phase I is to further develop this new method. The specific milestone is to demonstrate that it can give an average 6-fold increase in the quantity of human DNA that can be retrieved from stool. This study consists of 2 parts. The first is to develop the optimized procedure for capturing human DNA from stool. Care will also be taken to stabilize the stool DNA from degradation. The second part of Phase I is to demonstrate that the stated milestone can be achieved using this new method. The milestone will be quantitatively studied by comparing this new method with the existing method. The head-to-head comparison will be made by extracting human DNA from the stool samples of patients. It is noted that although this new method is developed for fecal DNA testing, it can serve as a universal method for capturing human DNA from any clinic specimens. [unreadable] [unreadable]